1 / 27

Use and Modification of Default SPFs in the IHSDM

Use and Modification of Default SPFs in the IHSDM. Mike Dimaiuta LENDIS Corporation. Options for using SPFs in IHSDM. Use Default SPFs “as is” Calibrate models, including SPFs Enter and use “your own” SPFs. Use Default SPFs “as is”.

raffaello-payton
Télécharger la présentation

Use and Modification of Default SPFs in the IHSDM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Use and Modification of Default SPFs in the IHSDM Mike Dimaiuta LENDIS Corporation

  2. Options for using SPFs in IHSDM Use Default SPFs “as is” Calibrate models, including SPFs Enter and use “your own” SPFs

  3. Use Default SPFs “as is” Run IHSDM Crash Prediction Module (CPM) without calibrating (i.e. with calibration factors = 1.0)

  4. Use Default SPFs

  5. Use Default SPFs “as is”

  6. Calibrate Models / SPFs Follow HSM Part C calibration procedure and enter factors via IHSDM Administration Tool

  7. Calibrate Models / SPFs

  8. Calibrate Models / SPFs

  9. Calibrate model / SPFs

  10. Calibrate model / SPFs

  11. Enter and use “your own” SPFs Via the IHSDM Administration Tool: “Crash Prediction” > “Model Data Sets”

  12. Enter and use “your own” SPFs Capabilities: For all SPFs, can change: Regression coefficients Overdispersion parameters Limitation: Can not change SPF functional form

  13. Enter and use “your own” SPFs After editing data, save as a new Model Data Set “configuration” and select when running CPM

  14. Enter and use “your own” SPFs Example: Multilane Rural H’way Estimate crashes using defaults Enter “My State’s SPFs” into Administration Tool Run CPM with modified SPFs to generate and compare results

  15. Estimate crashes using default SPFs

  16. Enter “My State’s” SPFs into Administration Tool

  17. Enter “My State’s” SPFs into Administration Tool

  18. Enter “My State’s” SPFs into Administration Tool

  19. Run CPM with modified SPFs

  20. Compare Results Estimated Total crashes using default SPFs: 27.84 Estimated Total crashes using “My State’s” SPFs: 27.62

  21. Summary No requirement for agencies to develop their own SPFs for IHSDM, but… IHSDM provides a mechanism for agencies to edit all default SPFs (coefficients and overdispersion parameters only) Either way can produce good results!

  22. Questions? For additional information: www.tfhrc.gov/safety/ihsdm/ihsdm.htm IHSDM Technical Support: IHSDM.Support@fhwa.dot.gov; (202)-493-3407 To download IHSDM software: www.ihsdm.org Shyuan-Ren (Clayton) Chen Clayton.Chen@fhwa.dot.gov; (202)-493-3054

More Related